Liquid level gauge



May 16, 1933. C. KNOBLOCH 1,909,545

LIQUID LEVEL GAUGE Filed- Oct. 19, 1929 Patented May 1s, 1933 l 1,909,545

UNITED STATES PATENT oFFlcE CARL KNOBLOCH, F -.A130112 OHIO LIQUID LnvnL euren,

Application meneame: 1s, 192s. semi No. 400.759.

This invention relates to gauges for liquid phragm 15, the upper fold of which is contanks to indicate the quantity of liquid nectcd by a nipple 16 to the lower end of the therein, and has reference more particularly nipple 14 so that liquid in the tank T may to gauges of the electric type. flow freely through the' registering nipples f The general purpose or object of the in` 14 and 1G into the interior of the diaphragm 55 vention is to provide a simple and effective and expand the latter by the weight of the electrical device for this purpose, actuated liquid. The bore of the nipple 14 preferably by the hydrostatic head of the liquid in the is comparatively small, so -that the diav, tank, and more particularly to provide an phragm will not be appreciably a'ected by *0 attachment for the bottom of the tank, inagitation of the liquid in the tank, such as 60 cluding a pressure-responsive diaphragm occurs in automobile fuel tanks. construction upon which the liquid in the An arm 17 is adjustably mounted by a set tank operates, and a variable resistance discrew 18 on a stud 19 secured to and dependy rectly operated by said diaphragm and aring from the bottom fold of the diaphragm,

ranged in circuit with a suitable meter calithe arm 17 being of non-conducting matebrated to indicate the quantity of liquid in rial. Attached to the outer end of the arm the tank, which meter can be located at a re- 17 is a metal contact arm 20, the free end ot mote point, the device being adapted to the which preferably carries a roller 21. The use of several meters at various points, if reinner wall 11 of the box is cut away opposite quired. the end of the arm 20, exposing the resistance The foregoing and other objects of the incoil, and the insulation of the wire of the coil vention are attained in the device illustrated is also removed at this point, so that the roller in the accompanying drawing and described 21' plays over and crosswise of exposed porf below; although it is to be understood that tions of the coil, as clearly shown in Fig. 4.

o thev invention is not limited to the specific The upper end of the resistance coil is elec- 75 form thereof shown and described. trically connected to an insulated binding Referring to the drawingM post 22 mounted in the outer wall of the box,

Fig. l is a diagrammatic View showing in and the contact arm 20 is connected by a elevation a liquid-containing tank and my wire 23 to a lower binding post 24 also y improved liquid level gauge applied thereto mounted in and insulated from the wall ot and electrically connected to a remote indithc box. To the two binding posts 22 and 24 eating meter. is connected a circuit lead wire 25, in which Fig. 2 is an enlarged vertical axial section latter is included a source of electrical curof the diaphragm box and diaphragm, showrent, such as a battery B and a meter 26, the ing the diaphragm in nearly collapsed posipointer of which responsive to variations in S5 tion. the current flowing through the circuit Fig. 3 is a view similar to Fig. 2, showing line 25. the diaphragm'in fully expanded position. In the operation of the device, current Hows Fig. 4 is an enlarged sectional detail on from one side of the battery through wire the line 4 4 of Fig. 3. 25, binding post 24, wire 23, arm 2() and its 90 Referring to the drawing, 10 designates roller 2l, the portion of the resistance coil as an entirety a double-walled box, the inabove the roller 21, binding post 22, and wire ner and outer walls 11 and 12 of which are 25 back to the other sideof the battery. The spaced to receive an insulated resistance coil meter is actuated by variations in the curd or rheostat designated by 13. Attached to rent, these variations depending upon the 9" the top wall of the box is a threaded nipple amount ot the rheostat or resistance coil in- 14 which, as shown in Fig. 1, may be screwed eluded in the circuit. When the tank is full, into the bottom wall of a liquid-containing the diaphragm is fully expanded, and subtank T. Housed within the box 10 is a presstantially the entire resistance coil is thrown sure-responsive self-contracting bellows diainto the circuit. This causes the meter to indicate full. As the level in the tank falls, the h drostatic head of the liquid decreases, and t e bellows diaphragm contracts more or less, thus cutting out some ofthe resistance and causin the meter pointer to travel toward the ?ma'rk. Where the device is used as' an automobile gasoline tgnu the How passage from'the tank into e iaphragm is small that the diaphragm is substantially unufected by the jolting and agitation of the liquid in the tank, and the movement of the indicator pointer is steady.

From the foreigoing it will be seen that my invention provi es a very simple, direct-acting gauge, in which inaccuracies, due to lost motion between mechanical parts are avoided, and indication of the quantity of li uid at remote points is effectively accom- Lillshed. Modifications of the invention may e resorted to within the scope of the a Y ponded claims, without departing from e spirit thereof.

I claim: y

1. A liquid tank gauge, includinga box having a nipple thereon for threading into an aperture in the. bottom of a tank, aselfcontracting bellows dahragm in the lbox operable by pressure of t e liquid in the tank through the nipple, the bore of the nipple being suciently small yto prevent appreciable response of the diaphragm to agitation of the liquid in the tank, Aa resistance coil encircling said diaphragm within said box, and a contact member directly mounted on said diaphragm and riding on and crosswise of'sallloil'dunk l' bev 2. 'qui uge com rising a x formed with spa outer an inner walls,

said inner wall having a slot, a self-contractingl bellows diaphragm housed in said box and adapted for connection to a tank, a resistance coil mounted inthe said box between said outer and inner walls and a contact arm attached to and insulated from the bottom member of said diaphragm and movable with the latter, the free end ofsaid contact -arm extending through the slot of said inner wall and movableacro said resistance coil.

3. A liquid tank gauge apparatus including a box having a nipple thereon for threading into anaperture in the bottom of the tank, a pressure responsive diaphragm construction in the box operable by the p ofthe li uid in the tank throu the-ni ple, a variab e resistance contact e ement irectl mounted on the diaphragm construction, an a variable resistance coll wound about the box, said contact ri on said coil.

A C L KNOBLOCH. 

